The present invention relates to a copper-based sliding alloy excellent in wear resistance and, more particularly, to a copper-based sliding alloy applied to sliding bearings, valve plates and the like.
A technique related to copper-based sliding alloys with increased wear resistance is disclosed in JP-A-4-88137.
In this conventional technique, a sliding alloy is obtained by mixing solid lubricants, such as graphite, molybdenum disulfide and lead, and hard particles of SiC, SiO.sub.2, Si.sub.3 N.sub.4, Al.sub.2 O.sub.3, TiC, WC, TiN, etc. with copper alloy powder and by hot extruding the mixture. It is disclosed that a sliding alloy excellent in wear resistance and anti-seizure property is obtained by blending appropriate amounts of these lubricants and hard particles in a well-balanced manner.
However, higher performance such as sliding property has been required in recent sliding materials. In the above conventional technique which involves dispersing lubricants and hard particles in a matrix of copper, anti-seizure property is obtained from solid lubricants and wear resistance is obtained from hard particles. Wear resistance and anti-seizure property are improved by the contents of solid lubricants and hard particles. For this reason, anti-seizure property deteriorates when the content of hard particles is raised to increase wear resistance, whereas wear resistance deteriorates when the content of solid lubricants is raised to improve anti-seizure property. Therefore, there have existed limitations to the improvement of these properties.